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practical. As usual, prevention offers the best solution to the
problem namely,
(a) to block or obstruct the entry of the ant,
(b) to keep premises clear and free from crumbs and scraps
of food,
(c) to seal holes and cracks through which ants could enter and
(d) to use an effective insecticide, preferably of a residual
nature.
Cockroaches. The cockroach (Blatta orientalis) and its smaller
relative (Blattella germanica) are well known for their destructiveness,
especially in relation to stored organic matter, ranging from
foodstuffs to book bindings. Food is rendered repulsive from
contamination not only with their faeces but also with the
secretion from their scent glands, and the cockroach is strongly
suspected of transmitting to man a number of pathogenic organisms
especially those of an enteric nature.
Cockroaches shun the light and are most active during the
night. Warmth, moisture, darkness and close proximity to food
supplies constitute favourable conditions for breeding.
As was to be expected most of the complaints received concerning
this pest came from bakehouses and the three large hospitals
in the Borough; very few originated from occupiers of dwelling
houses. The construction of such premises offers ideal breeding sites
in concealed and almost inaccessible places. Thorough investigation
and treatment with D.D.T. resulted in the infestations being considerably
reduced. In all, 101 treatments were effected involving
829 rooms and 5 external areas.
Clover Mite. Twenty-five complaints were received from tenants
in blocks of flats in various parts of the Borough and 9 further cases
were found during survey concerning small red or dark brown
insects (Bryobia praetiosa) found moving over walls and windows.
This was a reduction of 11 from the previous year.
The clover or gooseberry mite is harmless to humans and to
household property. It is vegetarian feeding on a wide range of
plants and shrubs and, in some instances, on trees. During the
summer months of July and August the adult females leave their
feeding grounds to seek winter quarters, emerging the following
April to lay eggs on plants in the vicinity. It is during these periods
of migration that they cause concern when they move from their
natural environment into nearby buildings. Some infestations in
fact were reported from houses and flats where natural breeding
conditions were non-existent but where a recent laying of turfs had
occurred in the immediate neighbourhood. On 34 occasions,